Picosecond-level signal edge pulse signal generation device and method

Abstract

The invention discloses a pulse signal generation device and method of a picosecond-level signal edge. The device comprises a signal control module, a signal edge conversion module, a saturation gain module and an amplitude control module. The signal control module is used for generating a pulse width control instruction, generating or receiving an initial source signal and sending the initial source signal to the signal edge conversion module, and generating an amplitude control instruction and sending the amplitude control instruction to the amplitude control module; the signal edge conversion module is used for converting the signal edge of the initial source signal to obtain an initial picosecond-level signal edge pulse signal and adjusting the width of the pulse signal according to a pulse width control instruction; the saturation gain module is used for amplifying the adjusted pulse signal, expanding the amplitude dynamic range of the initial picosecond-level signal edge pulse signal to the maximum extent, and obtaining a saturated picosecond-level signal edge pulse signal; and the amplitude control module is used for controlling the amplitude of the saturated picosecond-level signal edge pulse signal according to the amplitude control instruction to obtain the picosecond-level signal edge pulse signal.

Description

Technical Field

[0001] The present invention belongs to the field of electronic test instruments in electronic technology, and relates to a signal generating device, in particular to a pulse signal generating device and method with a picosecond-level fast rising time edge. Background Art

[0002] With the continuous development of the semiconductor manufacturing process and electronic technology, the bandwidth levels achievable in application tests and working circuits in various cutting-edge fields are constantly increasing. On this basis, with the wide application of optoelectronic technology, the advantages of high transmission speed and bandwidth brought by light as a transmission medium have gradually emerged, which also puts forward higher requirements for the bandwidth and signal quality of related devices and test instruments.

[0003] High-bandwidth systems can achieve faster signal transmission and processing, improve work efficiency and performance, and provide higher precision and faster test and analysis capabilities. However, the increase in the working bandwidth will also introduce more interference into the system, and the proportion of noise interference received by each device in the system relative to the signal itself will increase, resulting in a decrease in the signal-to-noise ratio, which will reduce the reliability and accuracy of the instrument and affect the performance of the system.

[0004] The bandwidth of the system and related devices can be measured by testing the rising time of the signals they transmit. The specific relationship is as shown in Equation 1. Therefore, the faster the rising edge of the signals that the related test instruments can receive and output, the more they can meet the test requirements of high-bandwidth systems. In addition, during the test process, the time uncertainty brought by noise is also directly related to the rising time of the signal. See Equation 2 and Figure 1 , at the same signal amplitude level, the faster the rising edge of the signal, that is, the steeper the slope of the signal edge, the smaller the influence brought by noise, the better the entire system can prevent various interferences, and the higher the test accuracy obtained. Therefore, the speed of the signal front edge of the test equipment becomes a core factor.

[0005]

[0006] A picosecond-level fast front signal generator is a device that can generate extremely fast pulse signals. The pulse width and signal rising edge of its output are both in the range of several to dozens of picoseconds. The picosecond signal generator has an extremely short pulse width, high-precision control ability, and flexible modulation function, and can achieve extremely high frequency stability and time resolution, and is suitable for fields that require high-precision and high-speed signal processing, such as optical communication, ultrafast lasers, semiconductor chip testing, radar systems and many other cutting-edge fields.

[0007] In an optical communication system, it is necessary to convert electrical signals into optical signals for transmission. By combining a picosecond fast-front signal generator with a high-speed light source, it can be used for time measurement, signal modulation, and spectral analysis in optical communication systems. In addition, ultrafast pulses can also meet the test requirements for verifying the transmission speed achieved by optical communication systems, enabling precise calibration and time-domain signal analysis, and providing key support for the performance optimization and improvement of optical communication systems. In the field of laser technology, the modulation bandwidth of modulated lasers has been able to reach a level of >20 GHz. The picosecond-front signal generator can be used as a high-quality electro-optic modulation signal to achieve high-speed modulation of modulated lasers, precisely controlling the time structure and sequence of laser pulses. In ultrafast spectroscopy, the picosecond pulse signal generator can be used to generate a laser light source with ultrashort pulses for studying and observing the ultrafast dynamic processes of substances. Additionally, in laser interferometry, the picosecond pulse signal generator can provide a high-precision time reference signal for time synchronization and data processing in laser interferometry systems. In the medical applications of laser technology, extremely short pulses also enable precise treatment of tissues during applications such as laser therapy and laser surgery. When it comes to radar systems, the picosecond fast-front signal generator can be used to simulate the echo signals of targets in radar systems. For example, when testing the response of a radar system to different target sizes and speeds, the picosecond fast-front signal generator can provide highly controllable echo signals to help verify the performance of the radar system. In the research and testing of optical sensors, the picosecond fast-front signal generator can generate high-speed pulse signals for calibrating and testing the extreme performance of optical sensors. For example, in a high-speed optical imaging system, a fast and precise trigger signal is required to capture transient events, and the picosecond fast-front signal generator can provide high-speed pulse signals as triggers. In the testing of semiconductor chips, the picosecond fast-front signal generator can be used to test the high-bandwidth signal transmission performance of semiconductor chips. For example, using picosecond pulse signals to compare and test the waveform quality and response time differences of the input and output ports of high-speed digital chips or communication chips. In terms of high-precision reference signals, the picosecond fast-front signal generator can provide extremely high-precision reference signals. For example, in physical experiments of large scientific installations, high-precision and synchronous time measurement and analysis of transient events are required at different experimental sites. Through the distribution or cascading of picosecond pulses, high-precision synchronous reference signals can be obtained at different experimental sites to meet the requirements of high-precision time measurement.

[0008] At present, based on direct digital synthesis (DDS) technology, combined with complex time-domain reflection and precise control circuits and related electronics design, there are already pulse signal sources that can achieve picosecond signal edges. However, in current devices, in order to implement processes such as frequency synthesis, digital-to-analog conversion, signal control, and signal output, complex component compositions and circuit designs are required, and there are relatively high requirements for heat dissipation and electromagnetic interference shielding. Therefore, the current picosecond signal edge pulse generation devices also require a large volume and have high power consumption, making it difficult to miniaturize and integrate the signal generation devices. At the same time, in order to ensure the performance and reliability of the device, precise control and monitoring designs are required in existing signal generation devices to avoid the operating state of the device exceeding the damage threshold of high-precision components. The highly complex manufacturing and calibration processes also make the cost of such devices extremely high, which also limits the wide application of this device in more industries to a certain extent. Summary of the Invention

[0009] In view of the problems existing in the technical solutions of existing picosecond signal edge pulse signal generation devices, the present invention proposes a new method for generating picosecond signal edge pulses and provides a picosecond signal edge pulse signal generation device, which is characterized in that it includes a signal control module, a signal edge conversion module, a saturation gain module, and an amplitude control module, as Figure 2 shown;

[0010] The signal control module is used to generate an initial source signal, which is used to control the time-related characteristic parameters of the pulse signal output by the picosecond signal edge pulse signal generation device, including frequency, duty cycle, or a time series with set application requirements, etc. At the same time, the signal control module is also used to implement parameter control and adjustment of the signal edge conversion module and the amplitude control module;

[0011] The signal edge conversion module is used to receive the initial source signal and the pulse width control instruction output by the signal control module, implement signal edge conversion of the initial source signal, use the discrimination chip with fast output drive in the module to accelerate the signal edge of the output pulse signal, obtain an initial picosecond signal edge pulse signal, and at the same time, according to the pulse width control instruction, adjust the width of the output pulse signal by controlling the DC level therein;

[0012] The saturation gain module is used to receive the initial picosecond signal edge pulse signal output by the signal edge conversion module, and realize high-gain amplification of the signal through a multi-stage stacked amplifier circuit and reach the saturation state, so as to expand the dynamic range of the signal amplitude of the picosecond signal edge pulse signal generation device. The degree of dynamic range expansion is determined by the 1 dB compression output power (P1dB) of the amplifier circuit;

[0013] The described amplitude control module is used to receive the picosecond-level signal edge pulse signal after saturation gain and the amplitude control instruction from the signal control module. The amplitude control instruction includes the attenuation parameter required for the attenuation circuit in the amplitude control module. The attenuation circuit realizes the amplitude control of the saturated picosecond-level signal edge pulse signal according to the set attenuation parameter.

[0014] Further, a field programmable gate array circuit (FPGA) and related supporting circuits are provided in part of the signal control module. The integrated hardware logic includes:

[0015] 1) Receive the signal setting instruction from the outside according to the requirements of signal parameters;

[0016] 2) Generate an initial source signal with corresponding parameters according to the signal setting instruction;

[0017] 3) Generate a DC level control instruction for the signal edge conversion module and an amplitude control instruction for the amplitude module according to the signal setting instruction.

[0018] Further, the signal setting instruction received by the signal control module comes from the external control terminal of the entire signal generation device, which contains all relevant information of the pulse signal with the required picosecond-level signal edge, including the duty cycle, repetition frequency (or set time sequence), and amplitude.

[0019] Further, a discrimination chip with a fast output driver is provided in the signal edge conversion module, which has the characteristics of fast output signal edge and is not affected by the input signal edge, and is used to realize the conversion of the picosecond-level signal edge of the initial source signal.

[0020] Further, the discrimination chip in the signal edge conversion module can receive the pulse width control instruction generated by the signal control module. The discrimination chip adjusts the output DC level according to the pulse width control instruction. The signal width of the converted picosecond-level leading edge signal output is consistent with the width corresponding to the amplitude of the initial source signal when the DC level is equal, and thus realizes the change of the signal width of the output signal by adjusting the DC level.

[0021] Further, a communication interface and a digital-to-analog conversion circuit are provided in the signal edge conversion module, which can receive the pulse width control instruction of the signal control module and set the corresponding required DC level based on the pulse width control instruction, and is used to realize the fine adjustment of the signal width based on the DC level.

[0022] Further, a group of cascaded low-noise distributed amplifier chips are arranged in the saturation gain module. The used amplifier should have a working bandwidth higher than that corresponding to the picosecond-level signal edge, and an output power dynamic range that meets the amplitude requirements. Among them, the last stage of the cascade operates in a saturated state to realize the expansion of the amplitude dynamic range of the converted picosecond-level leading-edge signal.

[0023] In addition, a numerically controlled attenuation chip is arranged in the amplitude control module, and a serial communication control circuit is matched. It can receive the control instructions of the signal control module and set the corresponding attenuation ratio according to the instructions to realize the control of the signal amplitude.

[0024] Further, the signal transmission between different modules is realized through a microstrip transmission line or a radio frequency connection line with precise impedance to ensure the signal quality of the picosecond signal edge pulse.

[0025] The present invention sets multiple signal extraction and coupling methods at the output end of the final picosecond signal edge pulse, and sets a bias circuit and a fan-out circuit that can be controlled by the signal control module to realize the selection and adjustment of the polarity, baseline level, and number of homologous paths of the output picosecond signal edge pulse.

[0026] The method and steps for the signal control module, signal edge conversion module, saturation gain module, and amplitude control module to cooperate to generate a picosecond-level signal edge pulse and achieve precise control thereof are as Figure 3 shown:

[0027] 1) The signal control module receives a signal setting instruction, generates a standard level initial source signal with corresponding parameters according to information such as the duty cycle and repetition frequency of the required picosecond signal, and sends it to the signal edge conversion module. And generate a control instruction for adjusting the attenuation ratio of the amplitude control module according to the amplitude information in the signal setting instruction, and transmit it to the communication interface of the amplitude control module; and generate a pulse width control instruction and send it to the signal edge conversion module;

[0028] 2) The discrimination chip in the signal edge conversion module generates a DC level that can stably and reliably trigger the initial source signal according to the pulse width control instruction. To ensure reliable triggering, this initially set DC level is often half of the maximum amplitude of the initial source signal. Receive the initial source signal, and realize the conversion of the initial source signal into a picosecond fast signal edge signal through the fast driver of the discrimination chip in the signal edge conversion module. Then, adjust the pulse signal width of the initial picosecond-level signal edge pulse signal according to the DC level generated by the pulse width control instruction, and send the picosecond signal edge pulse to be expanded in dynamic range after conversion and adjustment to the saturation gain module;

[0029] 3) Complete the bias and gate voltage regulation of the distributed amplifier chip in the saturation gain module, achieve lossless amplitude amplification of the picosecond signal edge pulse and reach the saturation state at the last stage, and maximize the amplitude dynamic range of the picosecond signal edge pulse generation device;

[0030] 4) The digital control attenuation chip of the amplitude control module receives the control instructions transmitted from the signal control module, sets the corresponding attenuation ratio according to the instructions, completes the amplitude adjustment of the picosecond signal edge pulse signal with full dynamic range, and finally outputs the picosecond signal edge pulse;

[0031] 5) According to the output signal result, further adjust the pulse width control instruction sent by the signal control module to the signal edge conversion module, and adjust the DC level of the signal edge conversion module to achieve fine adjustment of the signal width of the finally output picosecond signal edge pulse.

[0032] Furthermore, a variety of signal extraction and coupling methods are set at the output end of the finally picosecond signal edge pulse, and a bias circuit and a fan-out circuit that can be controlled by the signal control module are set to achieve the selection and adjustment of the polarity, baseline level, and number of homologous channels of the output picosecond signal edge pulse.

[0033] In addition, when there is an initial source signal carrying relevant parameters externally, it can also replace the signal control module and directly input it into the subsequent modules to generate a picosecond-level signal edge pulse consistent with the parameters of the external reference source.

[0034] Advantages of the present invention:

[0035] Compared with the existing technical solutions, the present invention no longer needs to use complex direct digital synthesis technology, complex time domain reflection, and precise control circuit-related electronics design. It obtains picosecond-level signal edge pulses through signal edge conversion and saturation gain. The developed picosecond-level signal edge pulse generation device can simplify the composition of the picosecond-level signal edge pulse generation device, make it more meet the requirements of miniaturization and integration, reduce the complexity and cost of its manufacturing and calibration testing processes, expand the application fields and usage scenarios of the picosecond-level signal edge pulse generation device, and rely on the high bandwidth and high time accuracy characteristics of the picosecond pulse signal to play a role in more industries. Description of the drawings

[0036] Figure 1 It is a schematic diagram of the influence of signal edge speed on time uncertainty.

[0037] Figure 2 It is a diagram for explaining the composition and functions of each part of the picosecond-level signal edge pulse signal.

[0038] Figure 3 It is a flowchart of the method for generating picosecond-level signal edge pulses and implementing control based on the device. Detailed implementation mode

[0039] The present invention will be further described in detail below with reference to the accompanying drawings. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0040] The present invention relates to a picosecond-level signal edge pulse signal generation device, which is characterized in that the original scheme is improved by using the methods of signal conversion and saturated gain. The composition and implementation method of this device are as follows:

[0041] The proposed picosecond-level signal edge pulse signal generation device mainly includes four parts: a signal control module, a signal edge conversion module, a saturated gain module, and an amplitude control module.

[0042] The main function of the described signal control module is implemented by a field programmable gate array circuit (FPGA). The signal control module receives the signal setting instructions sent externally according to requirements of the device. The sources of these instructions include, but are not limited to, the operations of experimental personnel on the control devices (such as screens, knobs, buttons, etc.) on the device panel or commands obtained from a host computer via network protocols (such as TCP, UDP, etc.) or serial ports (such as RS232, UART, SPI, etc.). Based on the signal parameter requirements in the control instructions, according to time-related parameters, including signal width (duty cycle), repetition frequency, or a time series with set requirements, etc., a standard level initial source signal with corresponding parameters is generated using the hardware logic specifically designed based on functions such as frequency division and data selector in the FPGA, and is transmitted to the signal edge conversion module part. On this basis, a control instruction for adjusting the attenuation ratio of the amplitude control module is generated according to the amplitude information in the signal setting instructions and is transmitted to the communication interface of the amplitude control module.

[0043] The main function of the described signal edge conversion module is to make the rising and falling times of the signal edge of the input signal faster. Devices that can achieve this function include, but are not limited to, discrimination chips with independent fast output drivers or dedicated adjustable limiter amplifier chips, etc. A reasonable transmission line or RF connection interface is set at the input end of the signal edge conversion module to avoid reflection and distortion of the initial source signal input caused by impedance mismatch. A DC level that can satisfy the reliable triggering of the initial source signal is set at the chip, so that the initial source signal completes the signal edge conversion to reach picosecond-level rising and falling times. The signal that has completed the signal edge conversion will be sent to the saturated gain module part.

[0044] The pulse signal after signal edge conversion is subsequently input into the saturation gain module section. Devices that implement the saturation gain function in this section include, but are not limited to, cascaded distributed low-noise amplifiers, etc. To achieve distortion-free amplification of picosecond signal edge pulses, the -3dB bandwidth of the distributed amplifier used should be >15GHz, and the 1dB compression output power (P1dB) should be greater than the corresponding required dynamic range. According to the requirements, the biasing and gating voltage of the multi-stage distributed amplifier chips in the saturation gain module are adjusted to make it have an appropriate amplification factor and reach the saturation state at the last stage, so that the picosecond signal edge pulse generation device can obtain a sufficient amplitude dynamic range.

[0045] The amplitude control module controls the amplitude of the pulse signal output by the entire picosecond signal edge pulse generation device through signal attenuation. Devices that play a role include, but are not limited to, digitally controlled attenuation chips and other signal attenuation devices or circuits that can externally control the attenuation ratio. The signal attenuation device receives the control instructions transmitted from the signal control module, sets the corresponding attenuation ratio according to the instructions, completes the amplitude adjustment of the picosecond signal edge pulse signal, and finally outputs the picosecond signal edge pulse.

[0046] Based on the output signal result, in the signal conversion module, the signal width of the finally output picosecond signal edge pulse can also be finely adjusted through its DC level; at the same time, different signal extraction and coupling circuits controlled by an electronic control switch are provided at the final output end of the picosecond signal edge pulse device, which can achieve DC and AC coupling. On this basis, a multi-way fan-out circuit is added, and a bias circuit based on bias-T that can be controlled by the signal control module is added to each path. Based on this, through the adjustment of the duty cycle and coupling method, combined with the bias voltage of the bias circuit, the selection and adjustment of the output number of picosecond signal edge pulse signals with any polarity, baseline level, and the same source can be achieved.

[0047] Although specific embodiments of the present invention are disclosed for illustrative purposes, the purpose is to help understand the content of the present invention and implement it accordingly. Those skilled in the art can understand that various substitutions, changes, and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the present invention should not be limited to the content disclosed in the best embodiments, and the scope of protection claimed by the present invention is subject to the scope defined by the claims.

Claims

1. A device for generating a pulse signal with a picosecond signal edge, characterized in that: It includes a signal control module, a signal edge conversion module, a saturation gain module, and an amplitude control module; The signal control module is used to generate an initial source signal according to the received signal setting instruction or receive the initial source signal and send it to the signal edge conversion module, and generate a pulse width control instruction and an amplitude control instruction according to the received signal setting instruction; send the pulse width control instruction to the signal edge conversion module, and send the amplitude control instruction to the amplitude control module; wherein the initial source signal is used to control the characteristic parameters related to the time of the pulse signal output by the pulse signal generating device of the picosecond signal edge; The signal edge conversion module is used to convert the signal edge of the initial source signal to speed up the signal edge of the output pulse signal and obtain an initial picosecond signal edge pulse signal; and then adjust the pulse signal width of the initial picosecond signal edge pulse signal according to the pulse width control instruction; The saturation gain module is used to amplify the pulse signal output by the signal edge conversion module, maximize the amplitude dynamic range of the initial picosecond signal edge pulse signal, and obtain a saturated picosecond signal edge pulse signal; The amplitude control module is used to control the amplitude of the saturated picosecond signal edge pulse signal output by the saturated gain module according to the amplitude control instruction to obtain the picosecond signal edge pulse signal.

2. The device according to claim 1, characterized in that A discrimination chip is provided in the signal edge conversion module, and the discrimination chip generates a DC level according to the pulse width control instruction; the discrimination chip converts the signal edge of the initial source signal to obtain an initial picosecond signal edge pulse signal, and then adjusts the signal width of the initial picosecond signal edge pulse signal according to the DC level, and uses the width corresponding to the amplitude of the initial source signal being equal to the DC level as the signal width of the initial picosecond signal edge pulse signal.

3. The device according to claim 1, characterized in that The signal control module is provided with an FPGA for generating an initial source signal of corresponding parameters according to the signal parameters in the signal setting instruction.

4. The device according to claim 1, characterized in that The output end of the amplitude control module is provided with a multi-channel fan-out circuit, each of the fan-out circuits is connected to a bias circuit, and each of the bias circuits is connected to the signal control module respectively. The signal control module controls the bias voltage of each bias circuit to realize the selection and adjustment of the output paths of pulse signals with arbitrary polarity, baseline level and homologous picosecond signals.

5. The device according to claim 1, characterized in that A group of cascaded low-noise distributed amplifier chips are arranged in the saturation gain module. The low-noise distributed amplifier chips have a working bandwidth higher than that corresponding to the picosecond signal edge. The last stage of the cascaded low-noise distributed amplifier chip works in a saturated state.

6. The device according to claim 5, characterized in that The -3dB bandwidth of the low-noise distributed amplifier chip is greater than 15 GHz, and the 1 dB compression output power is greater than the required dynamic range.

7. The device according to claim 1, characterized in that A numerically controlled attenuation chip is provided in the amplitude control module, which is used to control the amplitude of the saturated picosecond signal edge pulse signal by setting the attenuation ratio according to the amplitude control instruction, so as to obtain the picosecond signal edge pulse signal.

8. The device according to claim 1, characterized in that The characteristic parameters include the frequency, duty cycle and amplitude of the pulse signal.

9. The device according to claim 1, characterized in that The signal control module is connected to the signal edge conversion module via a microstrip transmission line or radio frequency, the signal edge conversion module is connected to the saturation gain module via a microstrip transmission line or radio frequency, and the saturation gain module is connected to the amplitude control module via a microstrip transmission line or radio frequency.

10. A method for generating a pulse signal with a picosecond level signal edge, the steps comprising: 1) The signal control module generates an initial source signal according to the received signal setting instruction or receives the initial source signal and sends it to the signal edge conversion module, and generates a pulse width control instruction and an amplitude control instruction according to the received signal setting instruction, and sends the pulse width control instruction to the signal edge conversion module, and sends the amplitude control instruction to the amplitude control module; 2) The signal edge conversion module converts the signal edge of the initial source signal to accelerate the signal edge of the output pulse signal to obtain an initial picosecond signal edge pulse signal; and then adjusts the pulse signal width of the initial picosecond signal edge pulse signal according to the pulse width control instruction; 3) The saturation gain module amplifies the pulse signal output by the signal edge conversion module, maximizes the amplitude dynamic range of the initial picosecond signal edge pulse signal, and obtains a saturated picosecond signal edge pulse signal; 4) The amplitude control module receives the saturated picosecond signal edge pulse signal, and controls the amplitude of the saturated picosecond signal edge pulse signal according to the amplitude control instruction to obtain the picosecond signal edge pulse signal; 5) According to the picosecond signal edge pulse signal output by the amplitude control module, the pulse width control instruction sent by the signal control module to the signal edge conversion module is further adjusted to adjust the DC level of the signal edge conversion module to achieve fine adjustment of the signal width of the picosecond signal edge pulse.

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